CARSON, Calif. – When is the actual result of an MLS Cup final very nearly reduced to a subplot? When the illustrious David Beckham has made it his MLS finale.

And it is quite possibly Landon Donovan’s MLS curtain call, too.

Global soccer’s most iconic figure of the last two decades concludes his six years in Major League Soccer in the league’s 17th MLS Cup. Beckham, 37, has already announced that he will take his preternaturally gifted right foot – is there one more free kick goal in that pricey boot? – and perform elsewhere after Saturday, if only for a short duration.

And what to make of Donovan, the 30-year-old attacker who is the national team’s all-time leading scorer (and on a march to be Major League Soccer’s all-time leading scorer), but who seems a little beaten by it all and keeps dangling the notion of retirement?

And we haven’t even gotten to the Houston Dynamo, a humble and hard-working club that tends to grind out playoff results like no other. The Dynamo, steered so ably by smoothly demanding coach Dominic Kinnear, is in its fourth MLC Cup in seven years.

Houston fell to L.A. in this same matchup last year, 1-0.

Don’t forget, this is the first final played under new MLS playoff rules that award host duty to the finalist with the best record. So the big home field edge goes to the Galaxy – never mind that the weather in Southern California looks and feels a lot like we’re all in rainy Seattle.

The game has a chance to look a lot like last year’s, when the Galaxy squeezed out a 1-0 win in a meeting of the very same teams. In the very same building. With roughly the same weather. So it could once again be frustratingly cautious, as finals tend to be. Plus, both teams are good at waiting out the other fellow, careful not to make a mistake while waiting to pounce on one.

On the other hand, this is a very different Houston Dynamo team. Added since last year’s final are right-sided attacker Oscar Boniek Garcia and ground covering midfield specialist Ricardo Clark. Plus, the team’s four-time MVP, Brad Davis, will be on the field this year. Last year’s loss came as Davis watched from the sideline, injured.

Somewhat forgotten is that Houston also played the 2011 final with four center backs across the defense. Andrew Hainault was on the right, Jermaine Taylor on the left; both were in fill-in capacity due to other injuries. Thus, Houston’s ability to attack up the flanks was severely pinched.

So the Dynamo has the opportunity to apply far more pressure on L.A. this year. “We should be a lot more aggressive this time,” midfielder Adam Moffat said. “Last year, we created very few real chances, to be honest.”

Kinnear’s men are as healthy as they’ve been in a long time. Clark and Moffat, the preferred central midfielders, are training at full capacity after some recent injury worries. Calen Carr is back on the field, too, giving Kinnear a more pacey option for selection at forward.

Striker Will Bruin has four playoff goals, just one behind MLS post-season leader Robbie Keane.

You cannot talk about the Dynamo without mentioning how dangerous Davis and his pinpoint set piece deliveries have been for years. In most estimations, the veteran lefty is the second best restart specialist in MLS – after Beckham.

Davis has contributed directly (scored or assisted) on 20 Dynamo goals over each of the last two years.

Said Beckham, about the run-up to his final MLS contest: “It’s been an enjoyable week…. I am quite an emotional person. I know I will feel more emotion probably the day of the game. Maybe the night before the game. But I am really excited about the game itself. To be in third MLS Cup final, especially one being played in our own stadium, I am excited. And it’s going to be special.”

Beckham has evolved into more of a support player this year. He can still ping the pretty passes accurately over 60 yards, and the Dynamo players know so. Clark will be tasked with applying early pressure on the former England captain. Beckham will idle a little deeper in the midfield, not making quite as many thrusts forward, not quite as many overlapping runs around the right side, etc. Whereas last year he was more a “playmaker-distributor,” this year’s Beckham’s role is more “distributor-playmaker.”

Donovan, as he has most of his career, has lined up recently as an outside midfielder or as a second forward alongside Irish international Robbie Keane. It’s mostly about whether Galaxy coach Bruce Arena prefers midfielder Christian Wilhelmsson or forward Edson Buddle in the starting lineup; Donovan will fill the other spot.

Arena has a choice to make at center back, where rookie Tommy Meyer or far more experienced A.J. DeLaGarza will start alongside commanding center back Omar Gonzales. DeLaGarza is training now but has not played in two months.

Mike Magee has become “Mr. November,” so nicknamed for his tendency to contribute the big playoff goals. His late runs into the penalty area from the left side tend to be expertly timed.

And speaking of movement around the penalty area, Keane’s choices on where to go find the ball and his ability to create defensive confusion over the last two or three months has been as good as any forward in MLS. Ever.

Keane (16 goals, 9 assists) and Donovan (9 goals, 14 assists) were MLS Best XI selections. Gonzalez almost surely would have been but for missing half the season through injury.

Is this the “last hurrah” for a uniquely starry Galaxy side? Donovan said they aren’t thinking about that. “Any team from year to year has lots of turnover. That’s the way sports are. That’s the way other leagues are. So we’re just excited about the game tomorrow. Not many teams have a chance to do what we have a chance to do, and we want to make the most of that.”

L.A. is attempting to become the first back-to-back league champions since Houston won in 2006 and 2007.

A Galaxy team with Beckham, Donovan and Keane at full rev, with Gonzalez properly policing the back line, would be extremely difficult to beat, especially at home. But all of that has not happened consistently in the playoffs.

Meanwhile, Kinnear-coached teams know just how to reach that final gear in the post-season. They managed to make things very hard on the Galaxy in last year’s final despite being severely under-strength.

Houston can expect to create a few chances. So will Los Angeles, with Keane at the tip-top of his game. Look for a close and fairly cautious match – and don’t be surprised if this one is 1-1 after 90 minutes, needing an extra 30 minutes and possibly even penalty kicks to declare a winner.